What is the usage of “try” in Java?

In Java, the try keyword is used to initiate the exception handling mechanism, usually in conjunction with the catch and finally keywords. The try block is used to encapsulate code that may throw an exception. If an exception is thrown in the try block, the program will jump to the corresponding catch block for exception handling. The finally block is used to execute code that needs to be executed regardless of whether an exception occurs.

The basic structure of try-catch-finally is as follows:

try {
    // 可能会抛出异常的代码块
} catch (Exception e) {
    // 异常处理逻辑
} finally {
    // 无论是否发生异常都需要执行的代码块
}

The code within the try block may throw different types of exceptions, the catch block can catch different types of exceptions and handle them accordingly. The code within the finally block will always be executed, regardless of whether an exception occurs. This is typically used for releasing resources, closing files, and other operations.

In Java 7, the try-with-resources statement was introduced to automatically close resources that implement the java.lang.AutoCloseable interface. An example is as follows:

try (BufferedReader br = new BufferedReader(new FileReader("file.txt"))) {
    String line = br.readLine();
    System.out.println(line);
} catch (IOException e) {
    e.printStackTrace();
}

In this example, the try-with-resources statement automatically closes the BufferedReader object after the try block ends, eliminating the need to manually close the resource in the finally block.